"Espacio Blanco" ; Wi-Fi con esteroides.

Technology view.

November 7th 2008 Wireless at WARP speed From Economist.com White space promises to put WiFi on steroids.

3WRAP = 27 times the speed of light.

HOW much would you pay for unlimited access to WiFi hotspots that stretched for miles instead of a few hundred feet, provided unbroken connections even deep inside buildings, and offered broadband speeds ten times faster than today's wimpy connections found in coffee shops, hotel lobbies, airport lounges and homes? How about nothing, or next to nothing? That could be on the cards within a couple of years, thanks to a decision taken this past week by America's Federal Communications Commission (FCC). After four years of deliberations— and staunch opposition from television broadcasters, makers and users of wireless microphones, and mobile-phone companies—the federal regulators voted unanimously on November 4th to allow a new generation of wireless gizmos to access the internet using the empty airwaves ("white spaces") between television's channels 2 to 51. The FCC could have auctioned off those frequencies—it raised $19.6 billion in March 2008 by auctioning blocks of frequencies above 700 megahertz that will be vacated when television switches from analog to digital broadcasting—but to its credit it opted to make them freely available. The decision is a huge win for public-interest groups and tech firms like Google, Microsoft and Intel, who believe the white-space transmission could bring broadband to poorly served parts of the country. They see it as America's last chance to build a "third pipe" capable of providing much-needed competition to today's broadband duopoly controlled by the phone and cable companies. As a bonus, white space could also provide improved communications for fire-fighters, police forces, ambulance crews and other emergency responders. Competition and community services aside, the FCC has other reasons for making the white-space frequencies free for public use. It hopes to replicate the wave of innovation that swept the wireless world a decade ago with the introduction of unlicensed WiFi devices using frequencies in the public 2.4-gigahertz band. Before WiFi came on the scene, the 2.4-gigahertz band was considered good for little more than cordless phones, microwave ovens and garage openers. In 2008 almost 300m WiFi-enabled devices will be sold; that number is expected to rise to a billion by 2012. Over the past decade, the industry servicing the sector has grown from nothing to become a $30-billion-a-year business. White space could be even bigger. The frequencies involved were chosen for television back in the 1950s for good reason: they travel long distances, are hardly affected by the weather, carry lots of data, and penetrate deep into the nooks and crannies of buildings. No surprise proponents have dubbed them "WiFi on steroids". Once the changeover from analog to digital broadcasting is complete, the television networks will no longer need the white spaces between analog channels to prevent interference from noise and other transmissions. Apart from digital broadcasts being far less vulnerable to interference, there's now plenty of frequency-hopping technology around for detecting digital broadcasts and avoiding them. That hasn't stopped television broadcasters from claiming interference will remain a problem if unlicensed devices are allowed to operate in the same part of the spectrum. They point to trials carried out by the FCC in the summer of 2007 with a pair of preliminary devices designed to operate in the television band's white spaces. The results were spotty, with one of the devices unable to detect the presence of digital television signals reliably. But the broadcasters are being less than sincere. For instance, in busy television markets like Los Angeles, the vacant slices of white-space spectrum account for a third of the airwaves used by broadcasters; in rural areas, they occupy anything up to three-quarters of the spectrum allocated to television. Broadcasters had hoped to annex this valuable resource abutting their channels and use it to sell additional information services. They are well aware, too, that the trials they say proved white-space devices impaired their broadcasts were flawed, and were subsequently repeated successfully. Microsoft (a member of the White Spaces Coalition along with Google, Dell, HP, Intel, Philips, Samsung and Earthlink) demonstrated the scanner in the device that caused the problem was damaged. In follow-up trials, a backup prototype worked perfectly, detecting even the faintest of digital transmissions with 100% reliability. The FCC later concluded that the prototypes proved interference could be eliminated by using spectrum-sensing and geolocation to detect any television transmissions in their vicinity. Whenever a television signal was detected, the white-space device would automatically switch off until out of range. As far as the FCC was concerned, there was therefore no valid reason why broadcasters should be allowed to keep their unused, but extremely valuable, white space. To put television viewers at ease, the FCC has made it clear that white-space devices—whether mobile phones, laptops, game consoles, music players or other appliances with internet connections—will be required to operate on no more than four watts of broadcasting power. They will also be restricted to channels 21 to 51, where there are fewer television stations. For good measure, the geolocation circuitry built into a white-space device will determine precisely where it is, and then interrogate a database containing the locations of all the television transmitters in the area. The device will be prevented from transmitting until given an "all clear" by the database. Google has proposed that white-space devices be blocked from broadcasting in channels 36 to 38 to protect both wireless microphones operating in that frequency, as well as channel 37, which is used for telemetry in medicine and radio astronomy. Apart from consumers, the biggest beneficiary from the FCC's decision to open the white-space spectrum for unlicensed use has to be Google. Recall it was Google that started the bidding in March for the highly prized block of 700-megahertz frequencies occupied by analog television's channels 52 to 69. In the process, Google persuaded the FCC to attach "open-access" conditions to the block. Whoever finally won the auction would then have to allow phones supplied by others to work unhindered on its network. In other words, users would no longer be restricted to the carrier's proprietary services, but would be free to roam the internet—and, naturally enough, use Google's search engines, maps and other advertising-supported services. Having achieved its objective, Google then backed out of the bidding, leaving it to Verizon to cough up $9.4 billion and AT&T $6.6 billion for various 700-megahertz licenses (see article). Now Google gets arguably an even more valuable bit of spectrum real estate effectively for nothing. Building a network of white-space transmitters would then be a small price for Google to pay for gaining much the same kind of market dominance in mobile search and services as it has long established on the desktop.

Open article at "The Economist" Web Site

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Softphone para smartphones.

November 15, 2008. How to Make VoIP Calls on a Pocket PC Using Express Talk. From WikiHow. The do it yourself manual. Want to utilize the cheap rates of VoIP (Voice Over IP) from your mobile device ?. If you have a Pocket PC or a device that uses Windows Mobile with an Internet/Network connection you can now make calls via VoIP with Express Talk's "Pocket Talk" application. Steps Download Express Talk for Pocket PC. Once you have downloaded the setup.exe to your PC or Mac you will need to install it on your mobile device. When the application has been installed on the mobile device you are ready to make calls. You can make free VoIP calls if you are connecting to someone else with a softphone installed on their PC or Mac (see below in the "tips" section). To make calls to a regular phone you will need a SIP Service Provider (see below in the "tips" section). Enter the number you want to call using the keypad on the application or you mobile device keypad and then click the green telephone button. If you know that a friend has Express Talk installed on their mobile device, Mac or PC you can even "page" them with the Intercom button, like a CB radio. Tips With Express Talk you could potentially call someone using their internet IP (eg. "bob@123.222.333.444") but this is not usually practical. It is much easier to use a friendly address like "bob@myphoneco.com". To have this you need to sign up with a SIP proxy service. This is almost always free to signup for and usually requires nothing more than an email address. Some of the companies also provide gateway services. This means cheap phone calls to ordinary (non internet) lines. They are particularly cheap for international calls since you only pay the local call rates.

Warnings Pocket Talk allows you to trial the application for 14 days before a license is required. Apparently a freeware version will be made available soon. Things You'll Need Pocket PC or Mobile device running Windows Mobile OS ARM CPU (this covers almost all models) Internet or network connectivity from the device SIP service Provider. Related wiki HowsHow to Setup Voice over Internet Protocol (VoIP) in Your Home

Express Talk VoIP Softphone. Arrived: Apr 24, 2007 Made by: NCH

Express Talk VoIP Softphone for Windows Mobile Pocket PC. Freeware download Summary: The Express Talk softphone works like a telephone to let you make calls through your computer. You can call anyone on the internet who has installed it (or any other SIP softphone). Calls computer to computer are always free. You can also call ordinary 'real' telephone numbers anywhere in the world. Requirements: Pocket PC Express Talk VoIP Softphone Description The Express Talk softphone works like a telephone to let you make calls through your computer. You can call anyone on the internet who has installed it (or any other SIP softphone). Calls computer to computer are always free. You can also call ordinary 'real' telephone numbers anywhere in the world if you sign with a VoIP gateway service company. See here for some recommended telephone gateway companies. Features Lets you make internet phone calls free direct PC to PC, or PC to phone via a VoIP SIP gateway provider. Supports up to 6 lines on the one phone with the ability to put calls on hold. Works with a headset or in speakerphone mode with just a standard microphone and set of speakers. Includes data compression (GSM, uLaw, ALaw, PCM and G726), echo cancellation, noise reduction, comfort noise and more. Uses the standard SIP protocol so it can link to a broad range of telephone gateways, SIP systems or other internet phone software. Click here for a list of SIP service providers. Can be configured to work behind NATs and Firewalls. Supports caller ID display and logging. Includes a phone book with quick dial. Integrates with Microsoft Address Book. Supports call transfer (Business Edition). Lets you record phone calls to wav (Business Edition). Allows up to 6 people to join one call using the Call conferencing feature (Business Edition). Allows for quicker and easier communication using the Push to talk intercom (Business Edition). Includes Do not disturb button (Business Edition). Is available for PocketPC so you can take your VoIP numbers with you wherever you go, Also features more advanced line configuration options with the Express Talk Business Edition softphone. Works with our VoIP Virtual PBx to create a LAN based PBx for offices or call centers. Used in conjunction with the VRS Call Recorder, this softphone can record and save phone calls to MP3, wav and more. Plays on-hold music to callers on hold. Can also link to the IMS On-Hold Messages Player Software to create professional mixes of music and messages on the fly.

© NCH Swift Sound

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